import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;

public class Demo8 {
    public static void main(String[] args) {
        try(OutputStream outputStream = new FileOutputStream("./output.txt")){
            outputStream.write(97);
            byte[] bytes = {97,98,99};
            outputStream.write(bytes);
        }catch (IOException e){
            throw new RuntimeException(e);
        }
    }
}
